G-protein βγ subunits determine grain size through interaction with MADS-domain transcription factors in rice

Qian Liu, Ruixi Han, Kun Wu, Jianqing Zhang, Yafeng Ye, Shuansuo Wang, Jianfeng Chen, Yajun Pan, Qi Li, Xiaopeng Xu, Jiawu Zhou, Dayun Tao, Yuejin Wu, Xiangdong Fu
Nature Communications, 2018, 9 : 852  DOI: 10.1038/s41467-018-03047-9;      追溯原文......本站官方QQ群:62473826

The simultaneous improvement of grain quality and yield of cereal crops is a major challenge for modern agriculture. Here we show that a rice grain yield quantitative trait locus qLGY3 encodes a MADS-domain transcription factor OsMADS1, which acts as a key downstream effector of G-protein βγ dimers. The presence of an alternatively spliced protein OsMADS1lgy3 is shown to be associated with formation of long and slender grains, resulting in increases in both grain quality and yield potential of rice. The Gγ subunits GS3 and DEP1 interact directly with the conserved keratin-like domain of MADS transcription factors, function as cofactors to enhance OsMADS1 transcriptional activity and promote the co-operative transactivation of common target genes, thereby regulating grain size and shape. We also demonstrate that combining OsMADS1lgy3 allele with high-yield-associated dep1-1 and gs3 alleles represents an effective strategy for simultaneously improving both the productivity and end-use quality of rice.

G蛋白βγ亚基通过与MADS转录因子互作,影响水稻籽粒大小

同时提高谷类作物的籽粒品质和产量是现代农业面临的主要挑战。本文我们发现水稻籽粒产量数量性状基因座qLGY3,它编码一个含有MADS域的转录因子OsMADS1,是G蛋白βγ二聚体下游的关键效应子。可变剪接蛋白OsMADS1lgy3会产生细长粒,提高稻谷的品质和产量。Gγ亚基GS3和DEP1与MADS转录因子保守的角蛋白样结构域直接相互作用,作为辅助因子发挥作用,增强OsMADS1的转录活性,协同反式激活共同的靶基因,继而调控籽粒大小和形状。我们还证明,将OsMADS1lgy3等位基因与高产量相关的等位基因dep1-1gs3聚合,可以同时提高水稻的产量和稻米品质。


基因列表
  粒长粒重主效控制基因 GS3
  叶状颖壳不育基因; MADS盒基因; MADS转录因子 OsMADS1; LHS1; AFO; LGY3
  G蛋白γ亚基; 直立型密穗基因; 直立穗基因 DEP1; DN1; qPE9-1; qNGR9